A crack team of cave divers will explore New Mexico’s famed Blue Hole underwater cave system this weekend.

The Advanced Diver Magazine Exploration Foundation will send a team down Blue Hole cave in Santa Rosa, New Mexico. The cave has already been partially mapped down to a depth of 225 feet, but it’s believed to be much more extensive and the team is carrying equipment allowing them to go as deep as 350 feet.

Every member of the team is an expert cave diver with at least 15 years experience. Each brings their own specialty in biology, survey, photography, cinematography, equipment, logistics, multimedia, or other skills in order to fully document the cave and produce material for a proposed documentary. The ADM team holds records for exploring the two deepest and longest underwater caves in North America with depths below 450 feet and linear passages of over seven miles.

Blue Hole is a popular spot for scuba diving but the entrance to the caves has been barred by a grate for decades due to the deaths of two cave divers who were exploring the system.

Cave diving is a dangerous sport that requires extensive technical knowledge and physical endurance. While I enjoy caving and will happily go to Iraq and Somaliland on vacation, you won’t see me cave diving. It’s too hardcore for me. Best of luck to the ADM crew!

Want to be an explorer? Want to see places nobody has ever seen? You have three options: become an astronaut, become a deep-sea diver or become a caver.

The first isn’t going to happen for a man my age and the second is expensive, so it’s a good thing I live in one of the best regions in the world to do the third. Cantabria in northern Spain has a large amount of karst, a type of stone that often has caves.

One of them is Luna Llena (“Full Moon”), which has yet to be fully mapped. In my fourth caving expedition in Spain I was part of a team that went to look for new passages. I was thrilled. Seeing unexplored parts of the subterranean world was one of the reasons I got into caving. I didn’t think the payoff would come so quickly.

Luna Llena is at the bottom of an abandoned galena mine from the 1920s. The miners were blasting with dynamite one day and opened up a hole into an unknown cave. It’s been regularly explored ever since but there are still many blank spots on its map.

The mineshaft slopes sharply down into the bedrock. Walking along an old narrow-gauge track past ore wagons and rusted equipment, we soon arrived at the cave. There were four of us, two experienced cavers who would be doing the bulk of the mapping, myself, and another relative newbie named Nacho. I quickly discovered that this would be the toughest cave I’d faced in any country.Karst often forms narrow, deep passageways, the product of underground streams cutting away the stone. These passageways can be five, ten, a hundred meters high. There’s no real floor, just a gradual narrowing until you reach water at the bottom. The only way to traverse these is a technique called “chimneying,” in which you straddle the passage with a hand and a foot on each wall. If it gets a bit too wide you press your feet against one wall and your back against the other. You keep tied into a rope running along the wall so you don’t risk falling into the abyss.

This workout led to a payoff – a low chamber filled with soda straws, thin little tubes hanging on the ceiling that eventually form stalactites. We had to crawl on our hands and knees below these beautiful formations for several minutes before getting to a place where we could stand up.

A little more exploring brought us to a long, high passageway. Several small tunnels led away from it, several blanks on the map. We picked one and crawled inside.

This is where it really got interesting. We were off the map in a place nobody had ever seen. Sadly I didn’t have my camera. My Instamatic died the previous week and I wasn’t going to risk my SLR in these conditions. Nacho brought his, but since he was behind me the only shots he got of me were of the bottom of my boots. The tunnel was too small for anything else.

It was almost too small for us to move. Crawling along in a military low crawl, the tops of our helmets scraping against the roof, we came to a spot where the tunnel pinched.

One of the more experienced cavers turned and looked at me.

“You sure you want to do this?” she asked. “Stop and think about it.”

“Of course I want to do it.”

“You’re not claustrophobic?” she asked.

“If I was claustrophobic I would have started freaking out ten meters ago.”

She shrugged and wormed her way into the tunnel. I gave her time to get through and then went in myself. The only way to enter this part was to have both arms stretched out ahead of me. Even then my shoulders barely made it through. I edged my way forward with my forearms and feet, the tunnel pressing in on all sides. Breathing became difficult. There wasn’t enough room to inhale fully, but I was exerting myself and needed the air. Every move was an effort. I wondered if I would make it through. I didn’t panic, though. My only worry was that Nacho was going to have to grab my boots and haul me out.

Any lingering doubt that I have claustrophobia was snuffed out when my headlamp suffered the same fate. An outcropping in the rock hit the power button and the tiny space I was in plunged into darkness.

It didn’t matter. I hadn’t been seeing anything but the rock an inch in front of my nose anyway. Continuing by feel, I made it to a slightly wider part of the tunnel where I could bend my arm and switch on my light. Ahead of me was an even tinier tunnel turning at an acute angle. The caver ahead of me called back.

“Come on through. It’s like a second birth!”

The birth canal I actually had to push off with my legs and force my body through. I exhaled, crushing my chest as flat as it could go. My head and arms emerged in a little cyst in which sat two of our team. Another push and my shoulders made it. A final effort to get the stomach through, swearing all the way to give up beer. I felt the cave walls pressing against my stomach and the small of my back and then I let out a tremendous fart. The cave literally squeezed it out of me.

Poor Nacho. He was right behind me and had nowhere to run. I hoped he didn’t asphyxiate. He was my ride.

We all gathered in the cyst, Nacho looking a bit green around the gills. During all this time our more experienced leaders had been mapping the passageway. Now we got a chance. This was basic mapping, with a compass, tape measure, and clinometer. It was meticulous work in cramped conditions, yet highly rewarding. All my life I’ve studied maps, especially old ones with their tempting blank spots marked Terra Incognita. And now here I was in Subterra Incognita.

I studied every fissure and formation, hoping to find another passage branching away form the one we were in. None were wide enough to push through. The tunnel soon turned back and rejoined one of the main mapped passageways. We’d mapped maybe a couple of hundred meters. In the annals of discovery this is a very minor footnote. I didn’t care. It made all the scrapes and bruises worth it.

So if you want to be an explorer, consider caving. It’s not as hard as you think. I’m 43 years old and only moderately fit. Chances are you can do what I do. If you live in the U.S., the best way to get into it is to join the National Speleological Society. With more than 10,000 members and about 250 local chapters (called “grottoes”), there’s probably a group near you.

Green Spain has finally emerged from a miserable winter into a glorious if unreliable springtime, so it’s time to get out and enjoy the region’s natural beauty.

The northern coastal strip of Spain consisting of Galicia, Asturias, Cantabria and the Basque Region has the best outdoor and underground adventures the country has to offer. Its combination of scenic hikes and extensive caves is thanks to the predominance of karst, a type of stone the weathers quickly with water. As you can see from the picture above, rain turns exposed karst into strange, picturesque shapes. When water flows underground it carves out long caves.

One of the best places to see this at work is the Parque Natural de Collados del Asón in Cantabria. Less than an hour’s drive from both Santander and Bilbao, this 11,700-acre natural park is cut through by the Asón River and several smaller streams. Those and the frequent rainfall have scoured the terrain into a series of gorges and cliffs. A network of trails provides lowland rambles past traditional farmhouses and challenging climbs up to rugged and snowy peaks. The dark mouths of several caves beckon to you from the trailside, but these aren’t places to explore without training and preparation.

The weather was glorious the day we went. When you have a fine day here in the north, you get outside. Luckily, you don’t need good weather to get some exercise. The next time I went out we were pelted with a chilly northern rain, perfect conditions to explore Green Spain’s other outdoor attractions – its caves.

Caving is big here, with several organizations and adventure travel companies ready to show you the ropes. And for many caves, ropes are what you’ll need. As water cuts through the stone, it often finds fissures and plunges downwards, gradually widening them into vertical shafts. Rappelling into Stygian darkness is one of the best thrills caving has to offer.

One cave where you don’t actually need ropes is Cotera Cave, not far from the famous prehistoric painted cave of Altamira, 20 minute’s drive outside of Santander. The entrance isn’t terribly inviting – an almost invisible trail snarled with brambles leads to a low opening where cows take shelter from the rain. Cows, being cows, have left more than their hoof prints behind.

%Gallery-186970%Picking out way past the cow patties we turned a corner and entered a large chamber. Sadly, the walls were covered with graffiti. The vandals weren’t very adventurous, though, and we soon left their ugliness behind.

Cotera is a wet cave. For much of the route we sloshed through ankle-deep water as more dripped on us from above. This action creates the formations that make caves so alluring. Cotera appears to be a fairly young cave since there aren’t many large stalactites or stalagmites. Instead, we had baby formations in the form of soda straws, which with enough water leaving mineral deposits on them will eventually grow into stalactites.

At times, the cave narrowed down into tiny crawlspaces we had to worm our way through. Often these shafts took lung-crushing right turns or plunged down at 45 degrees so that we scooted down slick clay into a welcoming puddle. In this sport a “taste of adventure” tastes like wet clay, and the grit gets stuck between your teeth.

Once the cave had covered us in grime, it decided to wash us off by making us crawl along an underground stream with a low roof. There was no choice but to get on our hands and knees and splash trough chilly water. We spotted a couple of underwater passageways leading off into the unknown.

We let them stay a mystery. Cave diving – a combination of spelunking and scuba diving – is extremely dangerous and best left for the truly crazy.

A team of Iranian spelunkers exploring an underground cave system near Mehriz, Yazd have made a surprising discovery. Last year, the group of cavers stumbled across a massive underground chamber and after taking careful and exact measurements of its size, the cave is now confirmed to be the fourth largest in the world.

This new cavern is part of the Ghar-e-Dosar cave system located in central Iran, which has been known about for some time and is a popular destination for cavers in the region. The system hasn’t been completely mapped however so new aspects of it are still being discovered. Last February a team of eight entered the largest chamber there and set about taking precise measurements of its total expanse. Those numbers have all been crunched now and what they found is simply amazing.

The subterranean room measures 1263 feet across and 869 feet wide, covering roughly the equivalent of 20 acres. The cavern slopes downward over its length starting with a height of about 230 feet and plunging as low as 469 feet at its deepest point. Those dimensions are large enough to put it above Majlis al Jinn cavern in Oman and slightly behind the Torca del Carlista in Spain on the list of the world’s largest cave rooms.

It should be noted that this chamber ranks as the fourth largest in terms of size for a single cavern. Ghar-e-Dosar isn’t nearly as large as Mammoth Cave National Park in Kentucky, however, which doesn’t have a single chamber that compares in size but does stretch for more than 400 miles of underground passageways.

As I’ve mentioned on this blog before, I’ve moved from Madrid to Santander, in Cantabria in northern Spain. This region is part of what’s often called Green Spain, made up of the four northern regions of Galicia, Asturias, Cantabria, and the Basque Country. I’m loving life by the sea and I’ve been busy exploring Cantabria’s countryside, which offers some of the best hikes in Spain. Green and mountainous, northern Spain is unlike most people’s popular conception of the country.

I discovered a local hiking group via a Couchsurfing friend. We go every other Sunday and the group also acts as an intercambio, or language exchange, which are very popular all over Spain. It’s a good way to practice your Spanish, French, German, English, Italian, or Portuguese. There’s also an Irish guy who insists on speaking to me in Gaelic because of my name. If he keeps it up I’m going to start speaking to him in Amharic.

My first hike with them was through the Reserva del Saja, a reserve in the cordillera Cantábrica. This is one a popular destination for hikers from Santander and is only about 40 minutes by car. The hike starts at Bárcena Mayor, a cluster of stone houses nestled in the woods by a mountain stream.

%Gallery-140381%From there we hiked along a dirt track through woods bright with fall colors. An amateur mycologist kept heading into the woods in search of mushrooms and soon had a sackful. Like in other parts of the world, some mushrooms in Spain are toxic and you shouldn’t pick mushrooms unless you know what you’re doing. He showed us one particularly nasty variety that will give you permanent liver damage if you eat it. After a long walk we humped over a steep ridge and on the other side saw a large pool fed by a couple of waterfalls. This made a peaceful stop for lunch.

When hiking with Spaniards, be prepared for their later eating hours. Our lunch stop was at about 2PM and some people commented that we were stopping too early. Another culture shock came when I brought out my practical wilderness lunch of a sandwich, chocolate bar, fruit, and water. Many of my hiking companions busted out elaborately prepared meals, fine cheese, even bottles of wine. The Spanish know how to live well, and don’t see why they should stop doing so simply because they’re miles from the nearest paved road.

My second hike through the cordillera Cantábrica was from the town of Ampuero, about half an hour’s drive from Santander. This is in the Ason-Aguera region. Our goal was to climb Mount Yelso, also also known as Mojon Alto, to see a prehistoric menhir, or standing stone. This mysterious ancient stone stands in a prominent location from which you can see the surrounding countryside as far as the sea.

Of course getting there was half the fun. The fall colors are wonderful in Cantabria at this time of year. We tramped through a forest past a mysterious cave entrance and a sinkhole hinting at another cave. This is one of the best regions for caving in Europe and in future posts I’ll be sharing my experiences under Cantabria. Some of these caves have prehistoric paintings dating back 10,000 years or more. Others go down more than a kilometer and if you want to see the whole thing you have to pitch camp and sleep underground. Cavers from other parts of Europe have been known to move here just so they can be closer to the amazing caving opportunities.

At times the forest opened up and we passed green fields where cows, horses, sheep, and goats grazed. We enjoyed sweeping views of the mountains all around and the play of light and shadow over the landscape as the shadows of the clouds passed overhead. The weather can be unpredictable in this part of the world so Cantabrians are in the habit of enjoying the outdoors any time the weather is favorable.

The hike ended, and all hikes should, with a trip to a local tavern before the short drive home.

If you’re passing through Santander, feel free to look me up (just Google me) and with enough prior notice I’d be happy to introduce you to the group and see that you have a fun hike in the mountains of Cantabria.